Evaluation of a soybean product fujiflavone P40 as an antiosteoporotic agent in rats

Potential use of barks of woody vascular plants in bone mending: A review

The use of synthetic drugs to overcome bone ailments causes severe side effects, but the application of herbals is helpful in maintaining bone health and accelerating bone mending. Currently, there is no oral allopathic medicine to hasten bone healing, though folk and traditional practices have adopted herbal to fasten the recovery from bone ailments. Earliest recovery is a universally desired phenomenon, especially for elderly people where many more cases of traumatic injuries are common along the compromised body immunity. The computerized database search engines, such as Google Scholar, PubMed, ScienceDirect, Springer Link, etc., and textbooks were used to collect all relevant information about barks for bone mending activity published from 1990 onwards using certain keywords such as bark, folklore/ traditional bone healing practices, and phytopharmacology. The results obtained were compiled to make this review and related information is tabulated herewith. Traditional herbal bone healing exists in every society in the world. The plant barks of a few species (e.g., Ficus religiosa, Prunus cerasoides, Terminalia arjuna, etc.) have outstanding significance for bone healing because of their special chemical composition and novel properties to reduce swelling, pain, soreness, and speedy recovery of functions. Mostly bark extracts are rich in polyphenols, and minerals, represented with antioxidant, immunostimulatory, antibacterial properties, etc. There is a diversity of bark utilization for bone healing from different plant species, globally, of which only a few have been phytopharmacologically deciphered. Validated bark ingredients as medicine or food supplements are more useful due to the least side effects. Entrepreneurs have a scope to use bioactive obtained from plant barks that have not been scientifically screened till now. The research focused on the commercial application of plant barks as green medicine needs fingerprints of bioactive and clinically validated data including the concentration of biomarkers in the blood (IC50) for reducing the healing period. Phytopharmacological screening of barks used in folk medicine and synthesizing the therapeutics at mega quantities in industries is an array of hopes for sustainable utilization of natural resources. The bio-stimulating knowledge of certain herbal ingredients will be helpful in the development of synergistic formulations for rapid bone mending.

The potential health benefits of the isoflavone glycoside genistin

Genistin is a type of isoflavone glycoside and has a broad range of health benefits. It is found in a variety of dietary plants, such as soybean, kudzu (Japanese arrowroot), and other plant-based products. Genistin has been described to have several beneficial health impacts, such as decreasing the risk of osteoporosis and post-menopausal symptoms, as well as anti-cancer, anti-oxidative, cardioprotective, anti-apoptotic, neuroprotective, hepatoprotective, and anti-microbial activities. It may also assist individuals with metabolic syndrome. This review summarizes some of the molecular impacts and prospective roles of genistin in maintaining and treatment of health disorders. The review could help to develop novel genistin medicine with significant health benefits for application in the nutraceutical and pharmaceutical fields.

Anti-Osteoporotic Effect of Soy Isoflavones Intake on Low Bone Mineral Density Caused by Voluntary Exercise and Food Restriction in Mature Female Rats

Female athlete triad (FAT) is an interrelationship between menstrual dysfunction, low energy availability with or without eating disorder, and decreased bone mineral density (BMD) in female athletes. The purpose of this study was to investigate whether isoflavone intake can prevent bone loss caused by voluntary wheel running under energy-restricted condition. We used a female rat model of osteoporosis for female athletes established previously. Fourteen female Sprague-Dawley rats (8-wk old) were fed ad libitum and had free access to wheels throughout the study. At 18 wk of age, the rats were divided randomly into the following groups: 1) running control (RC), 2) running energy restriction (RR), and 3) running energy restriction and isoflavone-fed (RR+Iso) groups. The RR group was 30% dietary restricted. The RR+Iso group was 30% dietary restricted and fed the diet containing 0.5% isoflavone powder (Fujiflavone P40). The experimental period lasted 31 wk. At the end of this experiment, BMD of the proximal femur in the RR group was significantly lower than that in the RC group. However, the BMD in the RR+Iso group was not significantly different from that in the RC group. Moreover, the plasma estradiol (E2) level in the RR and RR+Iso groups was significantly lower than that in the RC group. These findings suggest that isoflavone intake inhibited bone loss when the E2 level was low in female mature rat model. Our findings may reveal the possible novel role of isoflavone in osteoporosis among female athletes.

Protective Effects of Selected Botanical Agents on Bone

Osteoporosis is a serious health problem affecting more than 200 million elderly people worldwide. The early symptoms of this disease are hardly detectable. It causes progressive bone loss, which ultimately renders the patients susceptible to fractures. Osteoporosis must be prevented because the associated fragility fractures result in high morbidity, mortality, and healthcare costs. Many plants used in herbal medicine contain bioactive compounds possessing skeletal protective effects. This paper explores the anti-osteoporotic properties of selected herbal plants, including their actions on osteoblasts (bone forming cells), osteoclasts (bone resorbing cells), and bone remodelling. Some of the herbal plant families included in this review are Berberidaceae, Fabaceae, Arecaceae, Labiatae, Simaroubaceaea, and Myrsinaceae. Their active constituents, mechanisms of action, and pharmaceutical applications were discussed. The literature shows that very few herbal plants have undergone human clinical trials to evaluate their pharmacological effects on bone to date. Therefore, more intensive research should be performed on these plants to validate their anti-osteoporotic properties so that they can complement the currently available conventional drugs in the battle against osteoporosis.

Metabolite Profiling Reveals the Effect of Dietary Rubus coreanus Vinegar on Ovariectomy-Induced Osteoporosis in a Rat Model

The study was aimed at exploring the curative effects of Rubus coreanus (RC) vinegar against postmenopausal osteoporosis by using ovariectomized rats as a model. The investigations were performed in five groups: sham, ovariectomized (OVX) rats without treatment, low-dose RC vinegar (LRV)-treated OVX rats, high-dose RC vinegar (HRV)-treated OVX rats and alendronate (ALEN)-treated OVX rats. The efficacy of RC vinegar was evaluated using physical, biochemical, histological and metabolomic parameters. Compared to the OVX rats, the LRV and HRV groups showed positive effects on the aforementioned parameters, indicating estrogen regulation. Plasma metabolome analysis of the groups using gas chromatography-time of flight mass spectrometry (GC-TOF-MS) and ultra-performance liquid chromatography quadrupole-TOF-MS (UPLC-Q-TOF-MS) with multivariate analysis revealed 19 and 16 metabolites, respectively. Notably, the levels of butyric acid, phenylalanine, glucose, tryptophan and some lysophosphatidylcholines were marginally increased in RC vinegar-treated groups compared to OVX. However, the pattern of metabolite levels in RC vinegar-treated groups was found similar to ALEN, but differed significantly from that in sham group. The results highlight the prophylactic and curative potential of dietary vinegar against postmenopausal osteoporosis. RC vinegar could be an effective natural alternative for the prevention of postmenopausal osteoporosis.

Chinese herbal medicine for bone health

CONTEXT

Chinese herbal medicine (CHM) has been widely used in clinical practice to treat bone disease for thousands of years. They are cost-effective with fewer side effects and are more suitable for long-term use compared with chemically synthesized medicines.

OBJECTIVE

Chinese herbal formula prescribed among the CHMs is safe, and it is an alternative medicine for bone-related diseases such as osteoporosis.

METHODS

Science Direct and Google Scholar were used to search articles published. The input key words were CHM, osteoporosis, Chinese herbal formula, traditional Chinese medicine, single herb, multiple-herbs, and bone health. CHMs (single herb and formula) lacking sufficient proof and evidence in the literature were excluded and only those with high citation were retained.

RESULTS

A brief review was summarized to indicate the application and the potential mechanism of single herb formula and multi-herb formula in treating the common bone-related diseases such as inflammation, fracture, osteopenia, and osteoporosis.

CONCLUSION

In order to ensure safety and efficacy of all these CHMs, the prescriptions with single herb and multi-component formula must be verified and ensured by reliable pharmacological and toxicological methods. Much more effort needs to be done for studying the standardization, safety evaluation, and mechanism exploration of herb formula as well as confirming the compatibility of these herbs which make one.

Preventive effects of collagen Peptide from deer sinew on bone loss in ovariectomized rats

Deer sinew (DS) has been used traditionally for various illnesses, and the major active constituent is collagen. In this study, we assessed the effects of collagen peptide from DS on bone loss in the ovariectomized rats. Wister female rats were randomly divided into six groups as follows: sham-operated (SHAM), ovariectomized control (OVX), OVX given 1.0 mg/kg/week nylestriol (OVX + N), OVX given 0.4 g/kg/day collagen peptide (OVX + H), OVX given 0.2 g/kg/day collagen peptide (OXV + M), and OVX given 0.1 g/kg/day collagen peptide (OXV + L), respectively. After 13 weeks of treatment, the rats were euthanized, and the effects of collagen peptide on body weight, uterine weight, bone mineral density (BMD), serum biochemical indicators, bone histomorphometry, and bone mechanics were observed. The data showed that BMD and concentration of serum hydroxyproline were significantly increased and the levels of serum calcium, phosphorus, and alkaline phosphatase were decreased. Besides, histomorphometric parameters and mechanical indicators were improved. However, collagen peptide of DS has no effect on estradiol level, body weight, and uterine weight. Therefore, these results suggest that the collagen peptide supplementation may also prevent and treat bone loss.

Preventive Effects of Collagen Peptide from Deer Sinew on Bone Loss in Ovariectomized Rats

Deer sinew (DS) has been used traditionally for various illnesses, and the major active constituent is collagen. In this study, we assessed the effects of collagen peptide from DS on bone loss in the ovariectomized rats. Wister female rats were randomly divided into six groups as follows: sham-operated (SHAM), ovariectomized control (OVX), OVX given 1.0 mg/kg/week nylestriol (OVX + N), OVX given 0.4 g/kg/day collagen peptide (OVX + H), OVX given 0.2 g/kg/day collagen peptide (OXV + M), and OVX given 0.1 g/kg/day collagen peptide (OXV + L), respectively. After 13 weeks of treatment, the rats were euthanized, and the effects of collagen peptide on body weight, uterine weight, bone mineral density (BMD), serum biochemical indicators, bone histomorphometry, and bone mechanics were observed. The data showed that BMD and concentration of serum hydroxyproline were significantly increased and the levels of serum calcium, phosphorus, and alkaline phosphatase were decreased. Besides, histomorphometric parameters and mechanical indicators were improved. However, collagen peptide of DS has no effect on estradiol level, body weight, and uterine weight. Therefore, these results suggest that the collagen peptide supplementation may also prevent and treat bone loss.

Eucommia Leaf Extract (ELE) Prevents OVX-Induced Osteoporosis and Obesity in Rats

The cortex of Eucommia ulmoides Oliver is widely used to treat kidney deficiency in traditional Chinese medicine. Its leaves have recently been reported to have anti-obesity properties in metabolic syndrome-like rat models. Due to a sharp decline in estrogen production, obesity, together with osteoporosis, are common problems in postmenopausal women. In this study, we examined the potential effect of Eucommia leaf extract (ELE) in preventing osteoporosis and obesity induced by ovariectomy (OVX). Forty-six female Wistar rats were divided into six groups: Sham-Cont, OVX-Cont, and four OVX groups administered estradiol and different concentrations of ELE 1.25%, ELE 2.5%, and ELE 5%. Treatments were administered after ovariectomy at six weeks of age and continued for 12 weeks. OVX induced a significant decrease in the bone mineral density (BMD) of the lumbar, femora, and tibiae, together with a marked increase in body mass index (BMI). The administration of 5% ELE led to a significant increase in tibial and femoral BMD, as well as significantly increased bone-strength parameters when compared with OVX-Cont rats. According to the suppressed Dpd and increased osteocalcin concentrations in ELE 5% rats, we suggest that varying proportions of bone formation and bone absorption contributed to the enhanced BMD in the femora and tibiae. In addition, significant decreases in body weight, BMI and fat tissue in 5% ELE rats were also observed. These results suggest that ELE may have curative properties for BMD and BMI in OVX rats, and could provide an alternative therapy for the prevention of both postmenopausal osteoporosis and obesity.

Prevention of bone resorption by intake of phytoestrogens in postmenopausal women: a meta-analysis

Phytoestrogens as selective estrogen receptor modulators like compounds may consider as a therapeutic option in osteoporosis. In this regard, the effect of phytoestrogens on bone biomarkers was examined in several trials which their results are controversial. We aimed this meta-analysis to evaluate the net effect of phytoestrogens on bone markers. A thorough search was conducted from 2000 to 2010 in English articles. All randomized clinical trials were reviewed, and finally, 11 eligible randomized clinical trials were selected for meta-analysis. Totally 1,252 postmenopausal women were enrolled in the study by considering the changes of pyridinoline (Pyd), desoxypyridinoline (Dpyd), bone alkaline phosphatase, and osteocalcin concentrations in urine and serum after phytoestrogens consumption. The urine Pyd and Dpyd levels decreased significantly in phytoestrogens consumers. Effect size and effect size for weighted mean difference of urine Pyd levels showed -1.229171 (95% confidence interval (CI) = -1.927639 to -0.530703) and -9.780623 (95% CI = -14.240401 to -5.320845), respectively, a significant results in comparison to control group and significant results for Dpyd -0.520132 (95% CI = -0.871988 to -0.168275) and -0.818582 (95% CI = -1.247758 to -0.389407), respectively. Meta-analysis indicates that phytoestrogens intake can prevent bone resorption, but its benefits on bone formation are not significant. This favorable effect was observed in low doses and in at least 3 weeks of phytoestrogens intake.

Combined effects of soy isoflavone and fish oil on ovariectomy-induced bone loss in mice

Both soy isoflavone and n-3 polyunsaturated fatty acids are known to reduce the levels of bone-resorbing cytokines; however, the synergistic effects of these food ingredients have not been examined yet. This study was performed to elucidate the effect of concomitant intake of soy isoflavone and fish oil on bone mass in ovariectomized mice. Eight-week-old ddY female mice were subjected to ovariectomy (OVX) or sham surgery, and then fed an AIN-93G with safflower oil (So) as a control lipid source, isoflavone-supplemented safflower oil (So + I), fish oil instead of safflower oil (Fo) or isoflavone-supplemented fish oil (Fo + I) for 4 weeks. Femoral bone mineral density was significantly decreased by OVX; however, this decrease was inhibited by the intake of isoflavone and/or fish oil. Histomorphometric analyses showed that bone volume and trabecular thickness in the distal femoral trabecular bone were significantly lower in the So group than in the sham group, but those were restored in the Fo + I groups. The number of osteoclasts was significantly decreased by isoflavone intake. The increased rate of bone resorption after OVX was inhibited by isoflavone and/or fish oil. The serum concentration of tumor necrosis factor alpha was increased after OVX, but was significantly lower with the combination of isoflavone with fish oil than isoflavone or fish oil alone. The results of this study indicated that the intakes of soy isoflavone and/or fish oil might have ameliorating effects on bone loss due to OVX. Further, the concomitant intake of soy isoflavone and fish oil at a low dose showed better effects on cytokines related with bone resorption.

Acute and subchronic toxicity of FCD, a soybean extract combined with L-carnitine, in Sprague-Dawley rats

Soy products are primarily composed of proteins, phytochemicals such as isoflavones, soy lipids, and carbohydrates. Recently, soy isoflavones with L-carnitine were reported to exhibit anti-obesity effects in mice. FCD, a combination of soybean extract and L-carnitine, is a newly developed food substance. As a part of its safety assessment, acute and 13-week subchronic toxicity studies were performed in a total of 100 Sprague-Dawley (SD) rats. In the acute study, a single limit dose of 2000 mg/kg was orally administered to five male and five female rats. No adverse effects or mortality was observed during a 14-day period or upon gross pathological examination. In the subchronic study, FCD was orally administered in daily doses of 500, 1000, and 2000 mg/kg for 13 weeks, resulting in no mortality, and no changes in hematological and serum biochemistry parameters, gross pathology or histopathology. However, body weights of females were significantly decreased 10 weeks after treatment at an average of 2000 mg/kg. In addition, a slight decrease in mean food and water consumption was observed at the same dose level for 13 weeks. Therefore, the no-observed-adverse-effect-level (NOAEL) of FCD was considered to be 2000 mg/kg for male and 1000 mg/kg for female SD rats.

Soy isoflavones mitigate long-term femoral and lumbar vertebral bone loss in middle-aged ovariectomized mice

We evaluated the protective effects of soy isoflavones (SIF) against osteoporosis in middle-aged ovariectomized (OVX) mice. SIF (30 mg/kg or 60 mg/kg) or 17beta-estradiol (E(2)) was administered to OVX mice for 4 months after bilateral ovariectomy. We observed the biochemical markers of bone turnover, e.g., alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP), in serum. We also observed the bone mineral density (BMD) in femurs and lumbar vertebrae. In addition, we examined trabecular bone and interstitial cells in the femur using hematoxylin and eosin staining. The decrease in ALP levels and the increase in TRAP levels normally resulting from ovariectomy were suppressed by administration of 60 mg/kg SIF or E(2). Administration of 60 mg/kg SIF or E(2) also maintained the BMD, trabecular bone, and interstitial cells in OVX mice compared to those in pre-OVX mice. These results suggest that 60 mg/kg SIF effectively mitigates ovariectomy-induced osteoporosis in middle-aged mice.

The potential role of soyfoods in weight and adiposity reduction: an evidence-based review

Evidence concerning the relationship between soyfoods and weight loss was reviewed. Detailed searches of PubMed and Web of Science were performed to identify and evaluate evidence for or against four propositions related to soyfoods and weight loss (Data from in vitro, animal, epidemiologic, and clinical studies were evaluated and summarized). (1) Certain soyfoods will improve weight and/or fat loss when fed at isolcaloric levels (similar calories given across experimental conditions, but not necessarily at a level to maintain current body weight); generally supportive evidence in animal studies, but there is no compelling support in human studies. (2) Certain soyfoods will improve weight and fat loss when included as part of a diet by affecting caloric intake; limited supportive evidence in animal and human studies. (3) Certain soyfoods will prevent/improve risk factors related to glucoregulatory function and cardiovascular health during weight loss; some evidence supporting this proposition, but additional evidence is needed before conclusions can be made. (4) Certain soyfoods will minimize the loss of bone mass during weight loss; no data available pertinent to this proposition. Limitations in existing data make it difficult to reach conclusions regarding these four propositions. Overall, the current data suggest that soyfoods are as good as other protein sources for promoting weight loss and there is a suggestive body of evidence that soyfoods may confer additional benefits, but results must be carefully interpreted and additional evidence is needed before making firm conclusions concerning soyfoods and weight loss.

Administration of capsaicin and isoflavone promotes hair growth by increasing insulin-like growth factor-I production in mice and in humans with alopecia

OBJECTIVE

Insulin-like growth factor-I (IGF-I) plays an important role in hair growth. Capsaicin activates vanilloid receptor-1, thereby increasing the release of calcitonin gene-related peptide (CGRP) from sensory neurons, and CGRP has been shown to increase IGF-I production. We recently reported that isoflavone, a phytoestrogen, increases production of CGRP by increasing its transcription in sensory neurons. These observations raise the possibility that administration of capsaicin and isoflavone might promote hair growth by increasing IGF-I production. In the present study, we examined this possibility in mice and humans with alopecia.

DESIGN

Dermal IGF-I levels, immunohistochemical expression of IGF-I in the skin and hair regrowth were examined after capsaicin and isoflavone administration to wild-type (WT) mice and CGRP-knockout mice. Plasma levels of IGF-I and promotion of hair growth were evaluated in 48 volunteers with alopecia after administration of capsaicin and isoflavone for 5 months.

RESULTS

Subcutaneous administration of capsaicin significantly increased dermal IGF-I levels at 30 min after administration in WT mice (p < 0.01), but not in CGRP-knockout mice. Dermal levels of IGF-I were significantly higher in WT mice administered capsaicin and isoflavone for 4 wks than in those administered capsaicin alone for 4 wks (p < 0.01) and in those administered neither of them (p < 0.01). Immunohistochemical expression of IGF-I at dermal papillae in hair follicles was increased in WT mice administered capsaicin and isoflavone and in those administered capsaicin alone at 4 wks. Hair regrowth was clearly more accelerated in WT mice administered capsaicin and isoflavone for 4 wks than in those administered capsaicin alone for 4 wks and in those administered neither of them. Plasma levels of IGF-I were significantly increased from baseline levels in 31 volunteers with alopecia at 5 months after oral administration of capsaicin (6 mg/day) and isoflavone (75 mg/day) (p < 0.01), while they were not increased in 17 volunteers with alopecia administered placebo. The number of volunteers with alopecia who showed promotion of hair growth at 5 months after administration was significantly higher among volunteers administered capsaicin and isoflavone (20/31: 64.5%) than among those administered placebo (2/17: 11.8%) (p < 0.01).

CONCLUSIONS

These observations strongly suggested that combined administration of capsaicin and isoflavone might increase IGF-I production in hair follicles in the skin, thereby promoting hair growth. Such effects of capsaicin and isoflavone might be mediated by sensory neuron activation in the skin.

Estrogen and isoflavone attenuate stress-induced gastric mucosal injury by inhibiting decreases in gastric tissue levels of CGRP in ovariectomized rats

We have previously reported that CGRP plays a critical role in the reduction of stress-induced gastric mucosal injury by increasing gastric prostacyclin (PGI(2)) levels in rats. Estrogen has been shown to increase the production of CGRP in sensory neurons. Isoflavone has estrogen-like effects and is referred to as a phytoestrogen. Thus, we hypothesized that estrogen and isoflavone might inhibit ovariectomy (OVX)-induced decreases in gastric tissue levels of CGRP, thereby attenuating gastric mucosal injury. We examined these possibilities in the present study. The administration of estradiol and isoflavone for 4 wk completely reversed OVX-induced decreases in CGRP mRNA levels of dorsal root ganglion neurons (DRGs) in rats. OVX-induced decreases in gastric tissue levels of CGRP and 6-keto-PGF(1alpha), a stable metabolite of PGI(2), in rats were reversed by estradiol and isoflavone. Water-immersion restraint stress (WIR)-induced increases in gastric tissue levels of CGRP and 6-keto-PGF(1alpha) were inhibited in ovariectomized rats. This inhibition was completely reversed by estradiol and was partially, but significantly, reversed by isoflavone. WIR-induced gastric mucosal injury was exacerbated by OVX, which was reversed by estradiol and isofolavone. In vitro experiments using DRGs isolated from rats demonstrated that neither estradiol nor isoflavone enhanced CGRP release from DRGs, but the former enhanced it in the presence of anandamide, an endogenous agonist for vanilloid receptor-1. These observations suggest that estrogen and isoflavone might inhibit OVX-induced decreases in CGRP levels in DRGs by promoting transcription, thereby contributing to the attenuation of stress-induced gastric mucosal injury in OVX rats.

Anti-osteoporotic effect of Erythrina variegata L. in ovariectomized rats

The present study was designed to investigate whether Erythrina variegata L. (EV), which belongs to the leguminous family, exerted any beneficial effects on bone in ovariectomized rats. Daily oral administration of the EV extract at 300 and 600 mg/kg for 14 weeks to rats prevented the OVX-induced increase in the serum OCN, ALP, and urinary DPD levels. Histomorphometric analysis of the proximal end of the tibia showed that the EV extract prevented the estrogen deficiency-induced decrease in trabecular thickness and trabecular area, as well as restoring the increase in trabecular separation in a dose-dependent manner. Moreover, the EV extract improved the energy absorption and stiffness of the mid-shaft of the rat femur. Thus, the present study clearly demonstrated that EV could suppress the high rate of bone turnover induced by estrogen deficiency, inhibit bone loss and improve the biomechanical properties of bone in the OVX rats.

Royal jelly prevents osteoporosis in rats: beneficial effects in ovariectomy model and in bone tissue culture model

Royal jelly (RJ) has been used worldwide for many years as medical products, health foods and cosmetics. Since RJ contains testosterone and has steroid hormone-type activities, we hypothesized that it may have beneficial effects on osteoporosis. We used both an ovariectomized rat model and a tissue culture model. Rats were divided into eight groups as follows: sham-operated (Sham), ovariectomized (OVX), OVX given 0.5% (w/w) raw RJ, OVX given 2.0% (w/w) RJ, OVX given 0.5% (w/w) protease-treated RJ (pRJ), OVX given 2.0% (w/w) pRJ, OVX given 17beta-estradiol and OVX given its vehicle, respectively. The Ovariectomy decreased tibial bone mineral density (BMD) by 24%. Administration of 17beta-estradiol to OVX rats recovered the tibial BMD decrease by 100%. Administration of 2.0% (w/w) RJ and 0.5-2.0% (w/w) pRJ to OVX rats recovered it by 85% or more. These results indicate that both RJ and pRJ are almost as effective as 17beta-estradiol in preventing the development of bone loss induced by ovariectomy in rats. In tissue culture models, both RJ and pRJ increased calcium contents in femoral-diaphyseal and femoral-metaphyseal tissue cultures obtained from normal male rats. However, in a mouse marrow culture model, they neither inhibited the parathyroid hormone (PTH)-induced calcium loss nor affected the formation of osteoclast-like cells induced by PTH in mouse marrow culture system. Therefore, our results suggest that both RJ and pRJ may prevent osteoporosis by enhancing intestinal calcium absorption, but not by directly antagonizing the action of PTH.

Lowering effect of an isoflavone-rich fermented soybean extract on the serum cholesterol concentrations in female rats, with or without ovariectomy, but not in male rats

We examined the effect of administering an isoflavone-rich fermented soybean extract (FSBE) on the serum cholesterol concentrations in male rats and in intact and ovariectomized (OVX) female rats. Dietary FSBE decreased the serum cholesterol concentrations in intact female and OVX rats, but did not affect the concentrations in male rats. Dietary FSBE increased the hepatic total and esterified cholesterol contents in the intact female rats, but decreased them in the OVX rats. This hypocholesterolemic effect was not a simple estrogenic effect because it has appeared in some reports that estrogen administration decreased serum cholesterol both male and female rats. Dietary FSBE increased the hepatic low-density lipoprotein receptor (LDLR) gene expression in the intact female rats as has previously been reported from many studies, but did not affect that of the OVX rats. Further investigation is needed into the hypocholesterolemic mechanism of FSBE.

A hot water extract ofChlorella pyrenoidosareduces body weight and serum lipids in ovariectomized rats

The effects of a hot water extract of Chlorella pyrenoidosa, which contains chlorella growth factor (CGF), on the body weight, serum lipids, and the bone mass were evaluated using an ovariectomized rat as a model for postmenopausal bone loss. Rats were divided into four groups: sham-operated (Sham), Sham given the CGF solution, ovariectomized (OVX), and OVX given the CGF solution, respectively. Administration of the extract to OVX rats suppressed the body weight gain. After 7 weeks, the administration of the extract to the OVX group reduced increases in both serum total cholesterols and high-density lipoprotein (HDL) cholesterols. It also normalized the decrease of triglyceride level in the OVX group. The ovariectomy decreased the tibial bone mineral density (BMD) by 19%, and the administration of the extract to OVX rats did not inhibit this decrease. These results suggest that a dietary supplement of CGF may be useful to control the body weight and improve lipid metabolism of menopausal women.